20151320317 has 4 divisors (see below), whose sum is σ = 20234935996. Its totient is φ = 20067704640.

The previous prime is 20151320291. The next prime is 20151320353. The reversal of 20151320317 is 71302315102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71302315102 = 2 ⋅35651157551.

It can be written as a sum of positive squares in 2 ways, for example, as 13236732601 + 6914587716 = 115051^2 + 83154^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20151320317 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20151320291 and 20151320300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20151324317) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41807478 + ... + 41807959.

It is an arithmetic number, because the mean of its divisors is an integer number (5058733999).

Almost surely, 2^20151320317 is an apocalyptic number.

It is an amenable number.

20151320317 is a deficient number, since it is larger than the sum of its proper divisors (83615679).

20151320317 is an equidigital number, since it uses as much as digits as its factorization.

20151320317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83615678.

The product of its (nonzero) digits is 1260, while the sum is 25.

Adding to 20151320317 its reverse (71302315102), we get a palindrome (91453635419).

The spelling of 20151320317 in words is "twenty billion, one hundred fifty-one million, three hundred twenty thousand, three hundred seventeen".